diff --git a/jour11/jour11.lua b/jour11/jour11.lua
new file mode 100644
index 0000000..c00364f
--- /dev/null
+++ b/jour11/jour11.lua
@@ -0,0 +1,91 @@
+local function suivant(mot)
+    local len = mot:len()
+    local ret = mot:sub(1, len - 1)
+    if mot:sub(len, len) == 'z' then
+        ret = suivant(ret) .. 'a'
+    else
+        ret = ret .. string.char(string.byte(mot:sub(len, len)) + 1)
+    end
+    return ret
+end
+
+local function suite(mot)
+    local ret = false
+    local pred = nil
+    local i = 1
+    local c = nil
+    while not (ret and pred == nil) and i <= mot:len() do
+        c = mot:sub(i, i)
+        if pred == nil then
+            pred = c
+        elseif pred ~= nil then 
+            if string.byte(pred) == (string.byte(c) - 1) then
+                if ret then
+                    pred = nil 
+                else
+                    pred = c 
+                    ret = true
+                end
+            else
+                ret = false
+                pred = c
+            end
+        end
+        i = i + 1
+    end
+    if ret and pred == nil then
+        return true
+    else
+        return false
+    end
+end
+
+local function double(mot)
+    local ret = 0
+    local pred = nil
+    for c in mot:gmatch(".") do
+        if pred ~= nil and pred == c then
+            ret = ret + 1
+            pred = nil
+        else
+            pred = c
+        end
+    end
+    return ret
+end
+
+local function badChar(mot, char)
+    local ret = mot
+    local tmp = mot:find(char)
+
+    if tmp ~= nil then
+        if tmp == 1 then
+            ret = string.char(string.byte(ret:sub(tmp, tmp)) + 1) .. string.rep('a', ret:len() - tmp)
+        elseif tmp == ret:len() then
+            ret = ret:sub(1, tmp-1) .. string.char(string.byte(ret:sub(tmp, tmp)) + 1)
+        else
+            ret = ret:sub(1, tmp - 1) .. string.char(string.byte(ret:sub(tmp, tmp)) + 1) .. string.rep('a', ret:len() - tmp)
+        end
+    end
+    return ret
+end
+
+myInput = "cqjxjnds"
+fin = false
+
+while not fin do
+    myInput = badChar(myInput, 'i')
+    myInput = badChar(myInput, 'l')
+    myInput = badChar(myInput, 'o')
+    if suite(myInput) and double(myInput) >= 2 then
+        print(myInput)
+        fin = true
+    else
+        myInput = suivant(myInput)
+    end
+end
+
+
+-- une suite de 3 caractères au moins (abc par ex)
+-- ne doit pas contenir i l o
+-- doit avoir 2 doubles (aa et cc par ex)